Mold



Jain. 29, 1924. 1,482,145

J. E. PERRAULT MOLD Filed Jan. 18, 1923 N W m N N Inventor:

efosgah EBen/rault,

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latented Jan. 29, 1924.

UNHTED fiThTElfi PATENT @FFEQE.

JOSEPHE. ZPERRAULT, 0F WATEBTOWN, MASSACHUSETTS, ASSIGNOR T0 H001) BUB- IBEB COMPANY, OF WATERTOW'N, MASSACHUSETTS, A CORPORATION OF MASSA- CHUSE'ITS.

Application tiled January 18, 1928. Serial No. 618,490.

To all whom it may concern:

Be it known that I, Josnrn E. PERRAD'LT, a citizen of'the United States, and resident of Watertown, in the county of Middlesex and State of Massachusetts, have invented certain new and useful Improvements in Molds, of which the following is a specification.

My present invention relates to improvements in vulcanizing molds for forming hollow or cup-shaped articles from vulcanizable ms, and is particularly designed for use in the manufacture of hard rubber battery boxes or cells, though not necessarily limited to such use.

These boxes are usually made in multicell form, that is, they comprise a one-piece box with integral transverse partitions forming individual compartments for the cell units.

These boxes have, heretofore, been made, so far as I am aware, by the use of metal mold boxes comprising a base carrying detachable cores corresponding in number to the number of cells to be formed, and detachable sides and top bolted together and to thebase During vulcanization the rubber is forced against the fiat walls of the mold and core under pressure and with an air-tight, or suction, fit, and while it is a simple matter to remove the top and sides, due to their individual detachability, the removal of the. cores from their pockets has been a difficult matter, due to the suction fit,-

and this is rendered more diilicult by reason of the flat bottoms of the cavities.

The usual practice has been to detach the base from the cores, leaving them in position within the cell cavities, to thereafter insert a thin blade between the core or mandrel and the cell wall to permit entrance of air, and then remove the mandrel (or mandrels), after which they arereattached to the base.

The present invention aims to provide a mold which will render such operations unnecessaryand thereby lessen liability of damage to the molded article besides efiecting a material saving in labor; and the invention comprises the novel features of construction and arrangement and combination of parts hereinafter described, the precise nature and scope of the invention being ascertained and defined by the claims appended hereto.

An embodiment of my invention is illustrated in the accompanying drawings in which The figure is a longitudinal vertical section through a mold for making a three cell box, the core of one of the cells being shown in side elevation, the other two being in section with the vent closure of one in open position and of the other in closed position.

Referring byreference characters to this drawin the numeral 1 designates a battery box (s own for example as having three cells in place within the metal mold box 2, w ich comprises a base 2, side and end walls 2* and 2 and a top 2, it being understood that the battery box is molded in inverted position in, or relative to, the. mold. The mold parts described may be held together in any approved manner, as for example, by bolts, as shown. The cores or mandrels, for forming the cell cavities, are

thereto, or they may be detachable if de- A sired.

Each core or mandrel has a vent passage 3 which extends from the flat outer end a of the core lengthwise through the core and communicates with or is continued by a passage through the base. The vent passage should be closed during the vulcanizi operation, and preferably the closure shoul be efiected in such a manner as to leave the bottom forming surface a of the mandrel smooth and uninterrupted. To this end I make the outer end of the passage of contracted cylindrical form as indicated at a and provide within the main vent passage 3 a longitudinally movable rod or bar 4 having a reduced cylindrical end or projection 4* which will accurately fit and close the passage 0/ and the outer end of which, when in closing position, will'be flush with the surface a of the mandrel. Space is left between the body of the rod 4 and the main wallof the vent 3 for the passage of air, conveniently by making the rod of less diameter so as to leave an annular space, as shown.

As a convenient means of imparting lo. tudinal movement to the rod, I provide t e portion 4 which passes through the mold base, with screw threads which engage corresponding screw threads in the wall of the hole or passage through the mold base, as shown, the rod having a head 4 by which it may be turned and having also a longitudinal air passage 4.

It is desirable to provide means for limiting the movement of the rod in eitherdirection and this may be accomplished by providing an annular enlargement 1 in the mold base within which works a stop collar or member 4 fast on or integral with rod 4 which contacts with the inner and outer walls of the cavity when the valve is respectively opened and closed and thus limits the movement.

Having thus described my invention, what I claim is 1.. In a vulcanizing mold, a mold member, a core or mandrel carried thereby and having a vent passage therethrough, and means operable from the exterior of the mold for opening and closing said vent passage.

" 2. In avulcanizing mold, a mold member, a core or mandrel carried thereby and having a vent passage leading to the outside of said mold member, a rod movable longitudinally in said passage and having a portion to close said vent, and means for moving said rod.

3. In a vulcanizing mold, a mold member, a core or mandrel carried thereby and having a vent passage leading to the outside of said mold member, a rod movable longitudinally in said passage and having a portion to close said vent, said rod having a screw threaded portion engaging corresponding threads in the mold member.

4:. In a vulcanizing mold, a 'mold member, a core or mandrel carriedthereby and having a vent passage leading to the outside of said mold member, a rod movable longitudinally in said passage and having aportion to close said vent, said rod having a screw threaded portion engaging corresponding threads in the mold member, and msians for limiting the movement of the r0 v t 5. In a vulcanizing mold, a mold member, a coreor mandrel carried thereby and having a vent passage leading to the outside of said mold member, a rod movable longitudinally in said passage and having a portion to close said vent, said rod having a screw threaded portion engaging corresponding threads in the mold member, said mold member having an enlarged cavity around said rod, and said rod a stop member cooperating with the walls of said cavity.

In testimony whereof, I aflix my signs! ture. v

JOSEPH E. PERRAULT. 

